In digital control of a power converter device, an analog output voltage or the like is converted into a digital signal, the digital signal is subjected to a filtering process by a digital signal processing circuit, a timing signal is generated by a timing signal generating circuit, and switching elements such as transistors are turned on or off on the basis of the timing signal. In the digital control, by enhancing a resolution at the time of performing the analog-digital conversion, it is possible to accomplish high-quality control.